As a general rule, display devices in motor vehicles serve the display of information for the passengers of the vehicle, in particular the vehicle driver. Amongst others, display devices may display the vehicle speed, the vehicle rpm or the fill level of a fuel tank. As a general rule, these display devices are arranged in the field of vision of the vehicle driver, for example as a component part of an instrument cluster.
Common display devices have a display area which may be partitioned into an inner area and a lateral area in some displays. For example, numerals may be arranged on the display area. In the case of a speed indicator these numerals for example display the range of the possible vehicle speed.
In order to achieve a perspectively correct three-dimensional display of the numerals, for example in a planar display area of the display device, the numerals are displayed smaller at the part of the display area most to the rear as seen from the viewer. However, this reduction results in a poor read-out of the numerals by the viewer.
An improved visibility of the numerals and therewith also an improved read-out may be achieved by an inclination of the lateral area for example with respect to the inner area. DE 100 64 759 A1 disclose a instrument dial comprising a basic body, wherein the basic body comprises an inside ring area and a further outside ring area the exterior of which each is formed by a tapered surface, wherein the tapered surface of the outside ring area is steeper than that of the inside ring area. It is further disclosed that depending on their relevance level symbols are formed on differently inclined surfaces je that the indicating instrument and the instrument dial, respectively, all in all are better readable. However, in doing so no exact specification of the inclination angle is disclosed but only a relative reference from an inner area to a lateral area which indicates that the lateral area is steeper than the inner area. However, therewith a reference of the symbols arranged on the lateral area to the viewer, in particular the vehicle driver, is missing.
DE 10 2006 038 784 A1 discloses a display device of a motor vehicle comprising an instrument dial which has a support layer, wherein the support layer is formed three-dimensional, preferably may be deep-drawn. The support layer has an upwardly flanged edge at the perimeter which comprises a cocked horse shoe shaped scale dial. Also here a specification of the upwardly flanged edge with respect to the position of the viewer, in particular the eye position of the vehicle driver, is missing.
The printed matter “SAE J1052, Motor Vehicle Driver and Head Position, SAE, 400 Commonwealth Drive, Warrendale, Pa. 15096, USA” discloses a method for determining a head position volume of static head positions of a vehicle driver in passenger vehicles (class A) and in heavy goods vehicles (class B). Thereby, the head position volume is determined depending on a variable or fixed vehicle seat reference position and depending on a torso angle which is specified by a vehicle or vehicle seat manufacturer. Further, the printed matter shows that there is a correlation between the head position and an eye position.